Sealing of Developmental Pits and Fissures: I. In Vitro Study

Development and laboratory evaluation of a thermosetting polyurethane resin designed for use as a pit and fissure sealant was conducted. The material exhibited adhesion to enamel in excess of 1,300 psi. Radioautographs and scanning electron photomicrographs did not indicate leakage of isotope and showed an intimate contact between the resin and the fissure walls. The resin appeared to penetrate into the deepest fissures. The material is hydrolysis resistant; 90% of the original adhesive strength was retained after one year in 37 C water.